
function timeFormat(format = 'YY-MM-DD hh:mm:ss') {
    var time = new Date().getTime();
// function timeFormat(time,format = 'YY-MM-DD hh:mm:ss') {
    var date = new Date(time);

    var year = date.getFullYear(),
        month = date.getMonth() + 1,//月份是从0开始的
        day = date.getDate(),
        hour = date.getHours(),
        min = date.getMinutes(),
        sec = date.getSeconds();
    var preArr = Array.apply(null, Array(10)).map(function (elem, index) {
        return '0' + index;
    });////开个长度为10的数组 格式为 00 01 02 03

    var newTime = format.replace(/YY/g, year)
        .replace(/MM/g, preArr[month] || month)
        .replace(/DD/g, preArr[day] || day)
        .replace(/hh/g, preArr[hour] || hour)
        .replace(/mm/g, preArr[min] || min)
        .replace(/ss/g, preArr[sec] || sec);

    return newTime;
}
timeFormat(new Date().getTime());//2017-05-12 10:05:44
timeFormat(new Date().getTime(), 'YY年MM月DD日');//2017年05月12日
timeFormat(new Date().getTime(), '今天是YY/MM/DD hh:mm:ss');//今天是2017/05/12 10:07:45